Appearance library custom category name

[Neil_Cross]

So I'm trying to create a custom category in my companies custom ADSKLIB for appearances, I've no idea why as it doesn't make any difference to anything other than my own OCD, and I'm trying to create a category called Metal/Aluminium.  It won't let me, it blocks it because of the following reason:

And then it hit me, eh, hang on, the standard categories have those characters in them!

Dat logic yo.  I'm clearly not special or worthy enough yet to wield the power of the forward slash, please tell me what I must do to have this honor bestowed upon me.

Or is it just tough, I can't because reasons? It would nice if there was a way to copy the standard category names but it isn't the end of the world, very low priority.

Cheers